1. Field of the Invention
The present invention relates to an earphone antenna of a portable terminal. More particularly, the present invention relates to an antenna built in an earphone that can be connected to a portable terminal.
2. Description of the Related Art
Recently, in response to customers' high demand and with the development of information, communication, and semiconductor technologies, portable terminals are capable of providing Digital Multimedia Broadcasting (DMB) services. In order to display DMB channels, an antenna is needed to receive a DMB signal. Conventionally, an attachable/detachable antenna is mainly used for receiving the DMB signal while an earphone antenna replacing the attachable/detachable antenna is just beginning to be used.
FIG. 1 is a plain view illustrating a configuration of an earphone antenna of a portable terminal according to the related art.
Referring to FIG. 1, an earphone antenna 1 in a portable terminal is described. The earphone antenna 1 of the portable terminal includes a plurality of voice signal lines 10a and 10b, an insulating sheath 16 and an antenna line 18. Insulators 12a and 12b cover outer surfaces of the voice signal lines 10a and 10b, respectively, and a ground line 14 covers outer surfaces of the insulators 12a and 12b. The insulating sheath 16 covers an outer surface of the ground line 14 and the antenna line 18 having a given thickness θ winds around an outer surface of the insulating sheath 16 in a spiral form and at a given interval/width (WTH). An insulating jacket 5 covers an outer surface of the antenna line 18.
In the earphone antenna of the portable terminal described above, because the antenna line is formed on an entire earphone line at the given WTH, reception sensitivity can be greatly lowered depending on how the earphone is shaped according to a wearing state thereof.
Therefore, a need exists for an earphone antenna of a portable terminal having enhanced reception sensitivity even when a wearing state of the earphone of the mobile terminal is changed.